Acute meningococcal meningitis: analysis of features of the disease according to the age of 255 patients. Copenhagen Meningitis Study Group

Clinical and laboratory features of acute meningococcal meningitis according to age were studied in 255 patients. Whereas males accounted for three out of five patients aged 0-4 years, females accounted for three out of four patients older than 50 years of age. All patients had clinical signs of nuchal rigidity and fever. Patients older than 30 years of age had less frequent petechiae (62%) than younger patients (81%). Furthermore, elderly patients above 50 years of age were prone to an obtunded mental state and a prolonged disease course with fever. Without relation to age, 2/3 had purulent meningitis and 2/3 had marked peripheral leucocytosis (> 15 x 10(9) cells/l); 90% of patients had at least one of these findings. The cellular inflammatory response in peripheral blood indicated a bacterial aetiology in > 95% of the cases. More than 80% of children and adults had abnormal CSF biochemical findings, but the level of protein and the glucose ratio (CSF/serum) were positively and negatively correlated to increasing age of the patient, respectively: thus, in children these biochemical markers may be unreliable in the differentiation between a bacterial and non-bacterial aetiology. Thrombocytopenia (< 100.000 x 10(9)/I) was not associated with age, though the lowest platelet count was found in elderly patients. The case fatality rate was 7.5%, but neither age, sex nor sign of septicaemia was associated with fatality. Thrombocytopenia, a lowered coagulation index (< 0.5, factors II, VII, X), a moderate anaemia (haemoglobin < 11 g/dl), an obtunded mental state and a history of convulsions were poor prognostic factors; only anaemia was independently correlated to fatality so this should be considered as an important prognostic marker in the acute phase of meningococcal meningitis.

Measurement of antibodies against meningococcal capsular polysaccharides B and C in enzyme-linked immunosorbent assays: towards an improved surveillance of meningococcal disease

In order to improve the surveillance of serogroup B and C meningococcal diseases, enzyme-linked immunosorbent assays (ELISAs) specific for anti-B immunoglobulin M (IgM) and anti-C IgM and IgG antibodies were developed. The tests were evaluated by using paired sera from 122 patients with and 101 patients without laboratory evidence of meningococcal disease. Fifty-three of 67 patients (79%) with culture-confirmed serogroup B disease had an anti-B IgM antibody response; anti-B IgM levels waned rapidly in children < or = 4 years of age. Twenty-four of 25 patients (96%) with culture-confirmed serogroup C disease had an anti-C IgM and/or IgG antibody response (IgM, 92%; IgG, 68%). In patients without evidence of meningococcal disease, 19% of children < or = 4 years of age and 69% of those > 4 years of age had intermediate anti-B IgM titers. In contrast, only 1 and 5% of these patients had intermediate titers of anti-C IgM and anti-C IgG, respectively. The ELISAs were shown to be powerful tools for discriminating between serogroup B and C diseases in 96 to 100% of culture-confirmed cases. For 90% of patients with culture-negative meningococcal disease, a serogroup-specific diagnosis could be established by examination of paired sera in the ELISAs. As serogroup B and C meningococci account for practically all cases of meningococcal disease in industrialized countries, the availability of these tests may improve surveillance and prevention.

Report of the European DNA profiling group (EDNAP): an investigation of the complex STR loci D21S11 and HUMFIBRA (FGA)

This paper describes a collaborative exercise which was intended to demonstrate whether uniformity of DNA profiling results could be achieved between European laboratories using two complex short tandem repeat (STR) loci. The loci D21S11 and HUMFIBRA (FGA) were chosen because they are commonly used by different European laboratories. D21S11 has approximately 14 common alleles (f > 0.001), whereas HUMFIBRA has 19 common alleles. Laboratories were asked to test seven blood stains, one of which was a known control, and to report the results to the coordinating laboratory. The exercise demonstrated that complex STRs were amenable to standardisation.

[Posterior rectotomy--a minimally invasive procedure?]

This study included twenty-five consecutive patients, 12 men and 13 women, treated with a posterior approach to the rectum because of diseases in the mid and lower third of the rectum. Surgical indication included rectovaginal fistula in four patients, villous adenoma in 13 patients, villous adenoma containing carcinoma in three patients, primary carcinoma in four old high-risk patients and recurrent cancer in one old high-risk patient. There were only a few minor postoperative surgical complications, one wound infection and one rectal bleeding from the place of the excision. The bleeding was treated transanally. Three patients developed pneumonia. No patients died as a complication of the procedure. The posterior approach provides excellent exposure for complete removal of tumour in the mid- and distal part of the rectum, and the results of this study indicated that the technique has a place in the management of various benign and selected malignant conditions in the mid and lower third of the rectum. The procedure is easy to perform, safe with only a few minor complications and well tolerated even in old high-risk patients.

In vitro interaction of U2 snRNA with cytoplasmic 6S protein complexes

Interactions of U2 snRNA with anti-Sm precipitable proteins in RNA-free cytoplasmic complexes were analyzed. U2 snRNA was found to bind specifically with proteins in the 6S complexes but not in the 20S complexes. The binding activity was preserved using U2 snRNA having a mutated Sm binding site. Label-transfer experiments indicate that snRNA makes direct contact with anti-Sm precipitable proteins in the 6S fraction with apparent molecular mass of about 16 kDa. These data corroborate that proteins in the 6S core particle are the first to interact with snRNA, and suggest that the proteins recognize snRNA structures in addition to the Sm site.

The effects of fingermark enhancement light sources on subsequent PCR-STR DNA analysis of fresh bloodstains

This paper describes a study designed to investigate the effects of light sources used to enhance fingermarks on the subsequent polymerase chain reaction (PCR)-short tandem repeat (STR) analysis of bloodstains. Dried bloodstains on glass were exposed for up to 30 min to five different light sources: Argon ion laser, Polilight UV, Polilight green, Superlite, and shortwave UV. The bloodstains were subsequently analyzed using a quadruplex PCR system. It was found that treating the bloodstains with four of the five light sources had no appreciable effect on the results obtained from subsequent PCR analysis. However, exposure of the bloodstains to shortwave UV light for more than 30 s precluded the acquisition of results from PCR testing. Therefore, under casework conditions, it would be preferable to avoid exposing bloodstains, on which PCR typing is to be performed, to shortwave UV.

Effect of prednisolone on the systemic response and wound healing after colonic surgery

OBJECTIVE

To study the effect of preoperative treatment with a single high-dose glucocorticoid on the systemic and immunologic responses, wound healing, and convalescence after colonic surgery.

DESIGN

Double-blind, placebo-controlled, randomized trial.

SETTING

Department of surgery in a university hospital.

PATIENTS

Thirty patients scheduled for open colonic resection; 6 patients were excluded from the study (N = 24).

INTERVENTIONS

Patients were randomized to either of 2 treatment regimens: methylprednisolone sodium succinate 90 minutes before induction of anesthesia and epidural analgesia (group 1, n = 12), or placebo 90 minutes before anesthesia and epidural analgesia (group 2, n = 12).

MAIN OUTCOME MEASURES

Assessments of pain, pulmonary function, convalescence, and various injury and wound-healing factors were done several times until 10 days after surgery.

RESULTS

Conventional reduction in pulmonary function and mobilization was improved in group 1. Interleukin-6 and C-reactive protein levels increased significantly less in group 1, as delayed-type hypersensitivity was abolished in group 1. Plasma cascade system activations were significantly less pronounced in group 1. Reduction of collagen turnover was observed in group 1, but without detrimental effects on collagen accumulation.

CONCLUSION

Treatment with a single high-dose glucocorticoid before colonic surgery may improve postoperative pulmonary function and mobilization and reduce plasma cascade system activations, the inflammatory response, and immunofunction, but without detrimental effects on wound healing.

[Recurrence of inguinal hernia: ambulatory surgery under local anesthesia]

In order to assess the feasibility of repair of a recurrent inguinal hernia in unmonitored local anaesthesia in an ambulatory set-up pain scores and data on patient satisfaction were obtained from 76 unselected patients after 79 consecutive operations. Median age was 63 years, and 25%- and 75% quartiles were 49 and 72 years respectively. All operations were conducted in local anesthesia. Three patients stayed in hospital overnight after the operation. Pain: After one, six and 28 days 27, 14 og 7% respectively had severe pain during function (cough and/or rising). Satisfaction: 82% were satisfied with ambulatory surgery in local anaesthesia, 82% were satisfied with the analgesic therapy (tenoxicam and methadone), but one third needed supplementary analgesics during the first week (acetaminophen was recommended). It is concluded, that ambulatory repair of a recurrent inguinal hernia in unmonitored local anaesthesia is a safe and cost effective alternative to operation in general or spinal anaesthesia.

The validation of a 7-locus multiplex STR test for use in forensic casework. (II), Artefacts, casework studies and success rates

PCR-based DNA typing of biological evidence is now widely used in forensic analyses due to the obvious advantages of enhanced sensitivity, the ability to distinguish discrete alleles and efficacy with degraded samples. A multiplex short tandem repeat (STR) system has been previously developed which successfully co-amplifies six STR loci HUMTH01, D21S11, D18S51, D8S1179, HUMVWF31/A and HUMFIBRA (FGA) in conjunction with the X-Y homologous gene Amelogenin. This is known as the second generation multiplex system (SGM). Detection of the PCR products is undertaken on ABD 373A or 377 automated sequencers using denaturing polyacrylamide gels coupled with fluorescent-based technology. We have evaluated this system for routine forensic use and demonstrated that the technique is robust and reproducible under conditions consistent with those encountered in a forensic environment. A total of 132 stains from simulated and actual casework were analysed, together with relevant control areas and reference samples. The success rate was high with 76% of stains giving full profiles; we were also able to successfully detect and interpret mixtures. No mistyping was observed. A detailed examination of each of these profiles has assisted in the development of guidelines for casework interpretation. Although artefacts, stutter peaks and undenatured DNA were occasionally observed, these did not interfere with the accuracy of interpretation. In addition 38 samples, previously examined using the quadruplex system, were analysed with the SGM to enable a direct comparison to be made between the systems. The performance of the system with poor quality samples demonstrated its use as a rapid and powerful technique for individual identification.

Prognostic implications of ploidy and proliferative activity in the diffuse, aggressive non-Hodgkin's lymphomas

The International Index is a powerful predictor of outcome in the aggressive non-Hodgkin's lymphomas that is based solely on clinical features. Proliferative activity (% S-phase) measured by flow cytometry has been reported to have prognostic significance in many series and may represent a biologic correlate of clinical behavior that further defines prognosis. Flow cytometric analysis of cellular DNA content and proliferative activity (% S-phase) was performed on fixed paraffin-embedded biopsy specimens from 242 previously untreated patients with diffuse, aggressive non-Hodgkin's lymphomas entered on phase III intergroup clinical trials. The International Index was calculated for each patient based on stage, lactate dehydrogenase, performance status, number of extranodal sites, and age, as previously reported. The International Index consistently predicted response to therapy (P = .027) and survival (P = .007) in this series. DNA aneuploidy was shown in 57% of cases, but was not predictive of clinical outcome. The median % S-phase was 9.9 (median coefficient of variation, 3.6%), which was highly correlated with mitotic index (P = .0001). Although a trend associating low proliferative activity with good early survival and very high S-phase with a shortened survival was shown, International Index risk was the only significant predictor of survival in the multivariate analysis. Although proliferative activity quantitated by flow cytometric analysis of nuclei extracted from paraffin-embedded specimens is probably predictive of survival, it is a less powerful prognostic indicator than clinical parameters represented by the International Index and provides no additional prognostic information.

Phase II trial of interferon-alpha in locally recurrent or metastatic squamous cell carcinoma of the head and neck: immunological and clinical correlates

The objective of this study was to study the antitumor, host toxicity, and immunomodulatory effects of recombinant interferon-alpha 2b (IFN) in patients with recurrent or metastatic squamous cell carcinoma of the head and neck (SCCHN). Seventy-one patients with recurrent or metastatic SCCHN were entered into a phase II noncomparative randomized trial of IFN at two dosage schedules. Eligible patients with histologically proven SCCHN were randomized to receive low-dose IFN, 6 x 10(6) U/m2 daily x 3 every 4 weeks or high-dose IFN, 12 x 10(6) U/m2, 3 x/week. Pretreatment levels of natural killer (NK) activity, CD3, CD4, CD5, CD8, CD16, CD19, CD56, DR, and the CD4/CD8 ratio were evaluated for any relationship with survival. The toxicity encountered in patients receiving low-dose IFN was for the most part mild to moderate. With high-dose IFN, toxicity was greater with significantly more episodes of grade 3 and 4 toxicity encountered. Dosage reduction was required in the majority of patients receiving high-dose IFN. Of the four lethal complications, only one was thought to be possibly associated with therapy. Of the 32 evaluable patients receiving low-dose IFN, there were 1 complete response, 1 stable disease, 24 patients with progressive disease, and 6 unevaluable. Of the 29 evaluable patients taking high-dose IFN, there were 2 complete responses, 7 with stable disease, 16 with progressive disease, and 4 patients were unevaluable. Median survival in the two arms was similar (6.2 months). Because it was postulated that a more prolonged exposure to IFN might be needed for it to be effective, patients receiving > or = 6 weeks of therapy were evaluated. Median survival in that subset was 10 and 12 months for patients receiving low- and high-dose IFN, respectively. None of the immune parameters tested was a significant predictor of survival when evaluated in all cases entered into study regardless of therapy duration. No difference in baseline NK activity was noted between patients who received < 6 or > or = 6 weeks of IFN (p = 0.90). However, among the 35 patients who received > or = 6 weeks of therapy, a high baseline NK activity was a significant predictor of the duration of survival (p = 0.04). IFN was well tolerated in patients with recurrent or metastatic SCCHN. The higher incidence of toxicity encountered in the high-dose arm could be ameliorated by reducing the dose 50%. In patients receiving 6 or more weeks of therapy, elevated baseline NK activity was associated with increases in survival, suggesting that IFN may play an immunomodulatory role. Although the overall response rates were low, disease stabilization was noted, suggesting an antiproliferative, noncytotoxic role of IFN in this group of heavily pretreated patients.

Missing cause of death information in the analysis of survival data

Goetghebeur and Ryan proposed a method for proportional hazards analyses of competing risks failure-time data when the failure type is missing for some cases. This paper evaluates the properties of the method using data from a clinical trial in Hodgkin's disease. We generated several patterns of missingness in the cause of death in 'pseudo-studies' derived from the study database. We found that the proposed method provided regression coefficients and inferences that were less biased than those from other methods over an increasing percentage of missingness in the failure type when missingness is random, when it depends on an important covariate, when it depends on failure type, and when it depends on follow-up time. We present suggestions for study design with planned missingness in the failure type.

[Open surgery of choledochus in Denmark]

For each of the years 1991-1994 400, 209, 170 and 133 open common bile duct stone extraction were performed in Denmark, corresponding to 35%, 17%, 12% and 5% respectively of patients diagnosed with common bile duct stone. There was only little variation between the 16 hospital counties. The expected decrease in open common bile duct surgery corresponds to the introduction of several non-invasive methods for the treatment of common bile duct stones. To achieve further reduction in open surgery, centralization of the treatment of common bile duct stones is necessary.

Activation of protein kinase C in human uterine smooth muscle induces connexin-43 gene transcription through an AP-1 site in the promoter sequence

Myometrial connexin-43 gap junctions are scarce throughout gestation but appear in large numbers at term to facilitate contractions during labor. The mechanisms that regulate this process are incompletely characterized. This report investigates the effects of protein kinase C activation on the regulation of connexin-43 gene transcription in human uterine smooth muscle cells. In primary myometrial cells treated with phorbol ester, transient increases in c-Fos and c-Jun protein levels were observed at 2-4 h, followed by significant increases in connexin-43 protein levels at 6-8 h. Nuclear run-on transcription analysis showed an increase in connexin-43 transcription 3 h after phorbol ester treatment. AP-1 sites were identified in the sequence of the 5'-flanking promoter region of the human connexin-43 gene at 44 and 1000 base pairs upstream of transcription start. Transcription from a reporter plasmid containing the proximal human connexin-43 promoter was increased in transfected primary cultures treated with phorbol ester. Mutation of the proximal AP-1 site in the promoter abolished the phorbol ester-dependent transactivation. This work provides evidence that transcription of the human connexin-43 gene is induced through protein kinase C activation in uterine smooth muscle cells, and that the induction involves up-regulation and activation of c-Jun and c-Fos.

Rate dependence of regional cerebral activation during performance of a repetitive motor task: a PET study

Using repeated positron emission tomography (PET) measures of regional cerebral counts, we investigated the regional cortical activations induced in eight normal subjects performing eight different frequencies of fingertapping (0.5-4 Hz) with the right index finger. The task was auditorially cued and the performance recorded during the scanning procedure. Performance evaluation showed increased error rates, during fingertapping, of high and low frequencies, and the best tapping performance was measured in the midrange of frequencies. Significantly activated areas (p < 0.05) of normalized cerebral counts were located in the left sensorimotor cortex (MISI), right motor cortex, left thalamus, right insula, supplementary motor area (SMA), and bilaterally in the primary auditory cortex and the cerebellum. Statistical evaluation showed a significant (p < 0.01) and positive dependence of cerebral activation upon movement rate in the contralateral MISI. There was no significant rate dependence of cerebral activation in other activated motor areas. The SMA and the right cerebellar hemisphere showed a more uniform activation throughout the tapping frequency range. Furthermore, we found a stimulus rate dependence of cerebral activation in the primary auditory cortex. We believe that the present data provide useful information for the preparation and interpretation of future motor activation studies of normal human subjects and may serve as reference points for studies of pathological conditions.

Clearance of normal and type 2A von Willebrand factor in the rat

A model for the in vivo clearance of normal and mutant forms of human von Willebrand factor (vWF) has been established using catheterized rats. vWF clearance rates in rat plasma were determined by quantitation of reduced vWF subunits on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and multimeric vWF was analyzed using nondenaturing SDS-agarose gels. Normal vWF derived from human umbilical vein endothelial cells displayed a biphasic pattern of clearance, with half times of 35 minutes (T 1/2 a; SD 15. min.) and 245 minutes (T 1/2 b; SD 76. min.); metabolic clearance rate = 0.65%/minute. High molecular weight multimers of vWF were cleared more rapidly than dimeric vWF. vWF containing the S1613P mutation found in some type 2A von Willebrand disease (vWD) patients was observed to undergo proteolysis in vivo resulting in a reduction of high molecular weight vWF and concomitant appearance of rapidly-migrating satellite species, although the overall clearance rate of vWF antigen was similar to wild type vWF. These results provide direct in vivo evidence that the S1613P mutation causes the characteristic type 2A vWD phenotype. Full-length recombinant vWF produced from transfected Chinese hamster ovary cells was cleared at a similar rate to endothelial cell-derived vWF, and recombinant vWF devoid of O-linked carbohydrates was cleared significantly faster. vWF devoid of sulfate was cleared at a similar rate as wild type vWF, indicating the sulfate moiety of vWF does not regulate in vivo clearance. This animal model should prove useful in subsequent in vivo analysis of additional forms of vWD and in the development of protease inhibitor therapy for 2A vWD.

Growth factors and cytokines in uterine leiomyomas

Uterine leiomyomas, hard masses of smooth muscle-like tissue embedded in the myometrium, may be the most common tumors among humans. These tumors enlarge in as many as 30% of women over 30 years of age, cause significant morbidity, and are the most frequent indication for hysterectomy. Many researchers and clinicians have recently directed their attentions to understanding the etiology of these benign tumors, the conditions which cause their enlargement, and appropriate therapies which may be used as alternatives to hysterectomy. The ovarian steroid hormones estrogen and progesterone are known to play a central role in the pathology of leiomyomas. Both estrogen and progesterone contribute to the pathology of leiomyomas through gene regulation, but in opposing ways. During the follicular phase, estrogen maintains high expression of several genes which are normally expressed in the differentiated myometrium of pregnancy. During the luteal phase, progesterone can increase the mitotic activity of leiomyomas, particularly in younger women. Progesterone may act by inducing the production of growth factors and/or their respective receptors. This article surveys growth factors which may promote enlargement of susceptible leiomyomas. A potential role for cytokines in leiomyoma pathology is also discussed.

Terminal transferase expression in the differential diagnosis of acute leukemias. Eastern Cooperative Oncology Group

While the clinical significance of terminal transferase (TdT) detection in acute lymphoblastic leukemia (ALL) is uncontested, conflicting evidence exists for the prognostic relevance of this enzyme in blast cells from patients with acute myeloid leukemia (AML). The technical challenge of determining TdT in myeloid blast cells may be primarily responsible for those discrepancies in the literature. We present here the relative values of various standard approaches to the detection of TdT in ALL versus AML, including the slide staining technique, which served as the reference method, flow cytometry, and the biochemical enzyme assay.

10 years of pediatric liver transplantation

PURPOSE

Pediatric liver transplantation is an accepted therapy for end-stage liver disease, but little long-term data exist.

METHODS

From October 1984 to October 1994, 202 patients underwent a total of 225 liver transplantations. There were 98 boys and 104 girls, the average age was 5.1 +/- 4.9 (range, 0.2 to 19.1) years. Thirty (16%) were under 1 year of age. The diseases that required transplantation included biliary atresia (BA) (45%), metabolic liver disease (MLD) (9.9%), acute hepatic failure (6.9%), and Alagille's syndrome (AS) (5.4%). Originally the immunosuppression was cyclosporine- and steroid-based; the later regimens also included azathioprine and antilymphocyte preparations. All reported survival rates were derived from life-table analysis.

RESULTS

The patient survival rates at 1, 5, and 10 years were 76%, 70%, and 61%; the retransplantation rate was 11%. The respective graft survival rates were 71%, 63%, and 59%. There were 60 deaths; 48 (81%) occurred in the first year. These first-year deaths were from sepsis (20; 42%), central nervous system problems (5; 11%), intraoperative complications (4; 8%), lymphoproliferative disease (LPD) (2; 4%), rejection (2; 4%), primary nonfunction (2; 4%), and miscellaneous other causes (7; 15%). There were 12 deaths after the first year, from LPD (3; 25%), sepsis (1; 8%), rejection (2; 18%), cancer (1; 9%), secondary hepatic failure (1; 9%), cerebral vascular accident (1; 9%), or pre- or postoperative complications (3; 25%). Compared with the overall survival rate, patients with MLD had a better chance of survival (83%; P <.012) than did those with AS (45%; P < .001). The 5- and 10-year survival rates for patients with BA were 61% and 58%. Over the past 2 years, the survival rate has increased (87% v 72%; P < .05) as early septic deaths have decreased (from 2.6 to 1.0 per year).

CONCLUSION

Liver transplantation is effective treatment for end-stage liver disease. Decreasing the number of early septic deaths has improved the chance of survival, and better diagnosis and treatment of LPD would improve the late survival rate.

MLL tandem duplication and multiple splicing in adult acute myeloid leukemia with normal karyotype

Rearrangement of the MLL (myeloid-lymphoid or mixed-lineage leukemia) gene through a reciprocal chromosomal translocation is found in 5% of adult acute myeloid (AML) and 10% of pediatric acute lymphoid (ALL) leukemia. More than 25 different reciprocal chromosomal translocations, with an 11q23 breakpoint, fuse the MLL gene (also named ALL-1, HRX and Htrx1) to a second partner gene. These leukemias have poor prognosis and frequently have a monocytic, lymphoid or biphenotypic (myeloid and lymphoid) antigen expression in blast cells. Approximately 20-30% of patients diagnosed as having adult de novo, AML have normal chromosomes by metaphase analysis and the majority of these patients have good prognosis. With the use of reverse transcriptase-polymerase chain reaction (RT-PCR) technique and Southern blot analysis, we found that seven of 34 such patients (21%) had a tandem partial duplication of exons 2 to 6 or 2 to 8 of the MLL gene. These seven patients showed a median survival of 2.7 months, compared to a 6.8 months median survival for all other patients in the study. If confirmed on a large series of patients, our findings may help differentiate AML with normal karyotype and poor prognosis from those with normal karyotype and a more favorable prognosis.

Report on the third EDNAP collaborative STR exercise. European DNA Profiling Group

This report describes an inter-laboratory exercise completed on behalf of the European DNA Profiling (EDNAP) group. The exercise is one in a series designated to identify STR loci which could be used for harmonisation between participating European forensic science laboratories. Participants were asked to identify the alleles present in five bloodstains at the STR loci HUMTHO1 and HUMVWFA31/A. Two of the stains were prepared from mixtures of two different blood samples. There were no special instructions and each laboratory was requested to use the methodology normally employed for crime case investigations. All participating laboratories achieved the same results for both loci. In addition, the laboratories were also requested to report the results obtained from any other loci which would normally be used in crime case investigations. A comparison of these results showed some inter-laboratory variation.

Progestin represses human connexin43 gene expression similarly in primary cultures of myometrial and uterine leiomyoma cells

The mechanism by which progestin represses the expression of the human connexin43 (cx43) gene was analyzed in primary cultures of human myometrial cells, and for comparison, in primary cultures of uterine leiomyoma cells. Within 24 h, the levels of connexin43 (Cx43) protein in primary cells treated with progestin were reduced to about 50% of that in untreated cells, and these levels were maintained for up to 120 h. A plateau in the reduction of Cx43 protein levels was reached at progestin concentrations of 50-100 nM. No significant difference was found in a comparison of progestin-mediated reduction of Cx43 protein in autologous myometrial and leiomyoma primary cultures. Levels of cx43 mRNA levels also decreased to about 50% in myometrial and leiomyoma cells within hours after treatment with progestin, and these new levels were maintained for up to 48 h. Nuclear run-on transcription analysis showed that 100 nM progestin partially repressed transcription of the cx43 gene in both myometrial and leiomyoma primary cultures. The amount of decrease in cx43 transcription in cells treated with progestin was paralleled by a corresponding decrease in cytoplasmic cx43 mRNA levels. Progesterone receptor (PR)-mediated transcription was also determined to be similar in the two types of primary cells as evidenced by transient expression assays. Thus progestin down-regulates the expression of the human cx43 gene primarily by repressing transcription of the gene in myometrial cells, and it acts similarly in leiomyoma cells.